Many different types of materials are used in building. These include wood, concrete, stone, metal and drywall. It is frequently necessary to finish these materials by a grinding, sanding, or polishing process. For this reason there are many different tools specifically designed to accomplish the necessary finishing of a surface. Sometimes the smoothing is simply to make the surface more pleasant to the touch or appearance. On other occasions, it is designed to make the surface more receptive to coatings like paint. When the surface to be finished is a floor, it is relatively simple to do. A variety of floor grinders or polishers is available. A person simply stands with hands on the controls and moves the grinding machine back and forth over the surface to be finished. Ordinarily, the machine has an electric motor which drives a rotating pad on which a abrasive surface is placed. Care is required to make sure the grinding force is evenly applied across the surface—otherwise gouges, swirl marks, and the like can mar the surface for which a smooth and uniform finish is desirable. This process is more problematic when the surfaces which must be treated are a wall or ceiling.
Because of the difficulty in reaching ceiling surfaces, a number of expedients have been proposed. Whitsett, U.S. Pat. No. 3,948,005 discloses a ceiling grinding apparatus for use in grinding concrete ceilings. There is a portable support assembly with wheels, at least two of which are mounted on pivoting casters. There is a boom supported on a vertical arm. At one end of the boom is the grinding apparatus. The other end of the boom may be controlled directly by an operator or may be controlled by a control handle connected to the control end of the boom by springs, ropes or the like. A similar apparatus is seen in Ronvold, et al, U.S. Pat. No. 2,755,606 and McDonough, U.S. Pat. No. 2,670,577. Another variation of a ceiling sander or grinding apparatus for concrete or stone is seen in Woodward U.S. Pat. No. 2,049,935. What each of these machines has in common is a recognition that the kind of grinding apparatus required for a surface as hard as concrete or stone may be too heavy or unwieldy for comfortable use by an individual without the use of a support apparatus.
However, for most home construction, concrete ceiling or stone ceilings are unusual, if not unknown. More commonly, a building material known as drywall, which is a gypsum based material with a paper surface is used for the interior cover for the wood framing which constitutes the framework of a house. Drywall material is much softer and easier to work with than concrete, stone, or even wood. It readily receives paint with no necessity for preliminary sanding or treatment. However, the drywall comes in standard sizes. It must be cut and fitted together to form the walls or ceilings. It will ordinarily nailed into place and the nails be covered with a compound material called spackling which dries into a smooth surface. The spackling compound placed over the nails holes may require light sanding in order to match the spackling compound with the surrounding surface of the drywall. Where two pieces of drywall are joined ordinarily a piece of tape is applied over the joint with a spackling compound usually called “mud” used to cover the tape and to make the surface ready for application of paint. However, where the drywall seams or joints have been taped and muddied must be sanded in order to smooth the surface to match it to the surrounding drywall. Sanding tools are specifically designed and sold for this purpose.
A drywall sander is somewhat stereotypically designed with at one end a pivoting, rotating head on which a piece of sand paper or other grinding material is attached. An electric motor drives the pivoting, rotating head in rotational motion like a circular sander. A flexible hose connects this rotating head with a small vacuum container or canister which operates simultaneously with the rotation of the circular sanding head. This means that as the sanding is taking place, there is an automatic suction, vacuuming away the dust generated by the sanding. This simplifies cleanup and means that further dusting or vacuuming is unnecessary before paint is applied to the resulting sanded surface. The drywall sander itself is several feet long with the rotating head at one end of a handle with operating controls usually placed somewhere approximately between the two ends near the balance point on the arm of the sanding device. For up to eight foot ceilings, this device is sufficient to sand the seams in the walls and ceilings and can be used, albeit with some difficulty, to sand the ceilings and walls slightly higher than eight feet. However, many residential homes are being built with ten or twelve foot ceilings or with cathedral ceilings as high as fifteen feet. This requires the operator of the sanding device to stand on scaffolding or some other elevated surface. This is a cumbersome, time consuming, and sometimes dangerous process for the operator of the sander. Consequently, there is an unmet need for a device to be used with an existing drywall sander for sanding drywall or materials like drywall which require a light touch, where there is a limited surface to be sanded like seams or joints between sheets of building material, and where the surface to be sanded is higher than shoulder height.